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问题描述

我有Hotel实体:

  class Hotel {
City city
}

现在,我需要计算给定城市的酒店数量。
可以这样做:

  def hotels = Hotel.findAllByCity(city)
def cnt = hotels.size()

但它非常脏。它似乎与标准,它会更好,但我不知道如何实现它...

解决方案

有动态计数器以及域对象上的查找器:

  Hotel.countByCity(city)

更多详情请参阅,当然

I have Hotel entity:

class Hotel {
City city
}

Now, i need count of hotels with given city.It could be done in this way:

def hotels = Hotel.findAllByCity(city)
def cnt = hotels.size()

But it's very dirty way. It seems that with criteria it would be better, but i have no idea how to implement it...

解决方案

There are dynamic counters as well as finders on domain objects:

Hotel.countByCity(city)

More details in the user guide, of course

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10-28 06:38